Sewing and trimming mechanism



Dec. 15, 1959 F. L. BURGERT sswmc AND TRIMMING MECHANISM 2 Sheetsheet 2 Filed June 21. 1956 a M. i ll! 2 I: 2 a 1- 1mm M 2 m g Wan a, @II a l il w Em \NVENTOR FREDERICK L. BURGER? United States Patent 2,917,013 snwnvc AND TRIMMING MECHANISM Frederick L. Burgert, Valley Stream, N.Y., assignor t Ideal Pleating Co, New York, N.Y., a firm of New York Application June 21, 1956, Serial No. 592,921

4 Claims. (Cl. 112-127) The present invention relates to apparatus for simultaneously stitching and trimming superposed pieces of material, and in particular to an appliqueing device for stitching trimming to a piece of material along a prescribed stitch line and concurrently cutting away excess portions of the piece of material at one side of the stitch line.

In the manufacture of stitched assemblies, it is fre quently necessary to join superposed portions of material along a curved or scalloped edge of one of the pieces of material; and to trim away the excess portions of the other piece of material along the curved or scalloped edge corresponding to the stitch line. Heretofore, it has been deemed necessary to remove the excess portions by hand trimming to attain a neat and effective finish.

Many attempts have been made to employ mechanisms which concurrently stitch and trim to eliminate the necessity of hand trimming scallop-ed or curved edges of the stitched assemblies. These attempts fall generally into three broad categories. One approach has been to first complete the stitching, and then in a separate operation trim away the excess material. A second approach has been to precut the edge to conform generally to the scalloped or curved edge and then to feed the work with the respective edges in registry through the stitching mechanisms. A third approach has been to employ a rotary cutter at one side of the needle of the stitching unit to trim simultaneous with stitching. These approaches have not met with commercial acceptance, partly because of their inherent cumbersome nature, and in particular because of the difliculty of controlling the work. None provide the requisite flexibility to follow curves or scalloping, especially when there is a sharp change in direction. Such changes are encountered at the apex between adjacent scallops or at a corner when following an edge having rectangular cutouts.

It is broadly an object of the present invention to provide mechanisms for joining superposed pieces of material wherein stitching and cutting takes place simultaneously along paths determined by the steering motions imparted to the superposed pieces by the operator. Specifically, it is within the contemplation of the present invention to trim the bottom piece of a superposed fabric assembly without damage to the remaining superposed pieces, and in a manner calculated to be compatible with free movement of the assembly under control of the operator.

It is a further object of the present invention to provide a stitching and cutting mechanism which may be used to form a trimmed, stitch edge of any prescribed design, with the edge finished by the cutting away of excess material during the stitching operation.

In accordance with an illustrative embodiment demonstrating features of the present invention, a reciprocating cutter is arranged at one side of the vertically-operable needle of a sewing machine. The cutter is arranged to have its cutting edge disposed substantially in the same common vertical plane as the needle and is reciprocated in said vertical plane to achieve trimming simultaneous with stitching. A separator overlies the cutter and is arranged to separate the superposed pieces of material being fed through the sewing machine whereby the lower piece of material may be subjected to the action of the cutter during feed of both of said pieces through the sewing machine without effecting the upper piece or pieces. Advantageously the cutter and separator are constructed and arranged to present minimum obstruction to the free flow of the material through the sewing mechanism whereby the operator is free to steer the assembly along any prescribed path, and particularly those having sharp changes of direction.

The above brief description, as well as further objects, features and advantages of the present invention will be best appreciated by reference to the following description of a presently preferred, but illustrative embodiment, when taken in conjunction with the accompanying drawing, wherein:

Fig. 1 is a perspective view, with parts broken away and sectioned, showing stitching and cutting mechanisms embodying features of the present invention;

Fig. 2 is a sectional view taken substantially along the lines 2-2 of Fig. l and 22 of Fig. 3 showing the drive means for the knife of the trimmer;

Fig. 3 is a sectional view taken substantially along the lines 33 of Fig. 2 and along the line 33 of Fig. 5

showing further details of the present mechanisms;

Fig. 4 is an enlarged fragmentary plan view showing in detail the arrangement of the needle, the feed dog and the trimmer illustrated in Fig. 1;

Fig. 5 is a bottom plan view taken on Fig. 3 and looking in the direction of the arrow 5; and,

Fig. 6 is a perspective view diagrammatically illustrating the appliqueing of a piece of lace or similar trimming to a piece of material in accordance with the present invention.

Referring now specifically to the drawings, there is shown illustrative stitching and trimming mechanisms according to the present invention as applied to a 0011- ventional zig-zag sewing machine, which has been generally designated by the reference numeral 10. Included in this class of sewing machines are those manufactured by Singer and bearing the identifying class number 107W. However, it will be appreciated from the following detailed description that the present invention finds application to other types of zig'zag machines, as well as to conventional lock-stitch sewing machines. The type of machine employed will of course depend upon the required stitching operation; and therefore it is appropriate that the mechanisms described hereinafter be limited to the application of the present mechanisms to a typical machine.

The zig-zag sewing machine 10 includes: a base or throat plate 12 which is affixed to the base or bed of the sewing presser foot 20 which is normally spring biased into contact with the feed dog 16 and provides an area abutment therewith. In this illustrative form of the invention, the abutment or leg 22 of the presser foot has been partially cut away to aid in the free fiow of the material through the sewing machine. The needle 18 is carried by a needle bar (not shown) which is reciprocated vertically and oscillated laterally across the line of feed to produce the well known zig-zag stitch, as is conventional in the art. As seen in Fig. 2, the needle 18 moves between the limit positions, illustrated by the full and broken lines respectively.

The feed dog 16 is driven through a four-motion feed Patented Dec. 15, 1959 length. During this forward feeding stroke the uppermost face 16a of the feed dog, which is usually provided with fine pyramidal-shaped teeth, is above the uppermost face of the throat plate 12. During the return stroke of the feed dog, the same is retracted below the general level of the throat plate. The four motion drive includes a feed dog carrier 24 which extends generally transverse of the machine. As seen best in Fig. the carrier bar 24 forms part of the cam drive, generally designated by the reference numeral 26. In response to movement of the cam drive 26 in the conventional manner, the feed dog is reciprocated through its four motion feed path.

In accordance with the present invention, a verticallyreciprocating cutter 30 is arranged at one side of the needle and at a prescribed distance therefrom. As illustrated in Fig. 2, and as will be appreciated from a description of a typical sequence of operation, this spacing is selected to allow for the requisite lateral displacement of the needle 18 in forming the zig-zag stitching, and to provide for a'sufficient body of material between the cut edge and the adjacent side of the stitching to assure support in the material for the stitching. The cutter 30 is reciprocated in timed relation to the operation of the four-motion feed dog 16 and from the very same mechanisms which impart the motion to the feed dog. Specifically, a C-shaped yoke 32 is arranged to extend be neath the throat plate and to straddle the feed dog, as seen best in Fig. 5. The yoke is pivotally mounted by studs or bolts 34, 36 which extend through bearing ends 38, 40 on the yoke. The studs are supported on depending pairs of ears 42, 44, 46, 48 carried on the underside of the throat plate. The studs or shaft 34, 36 are aligned and extend transverse to the direction of feed of the matetrial. The yoke 32 carries a forwardly extending bifurcated block 50 having a horizontally extending cam follower slot 52 which is open at its lowered end. The knife 30 has a supporting arm 54 which mounts the same on the block 50. Riding in the cam follower slot 52 is a circular cam element 56 which is carried on an extension 58 of the camming member 26. The cam and follower connection to the block or yoke St! is effective to reciprocate the knife 30 vertically, as indicated by the directional arrows on the supporting arm 54 in accordance with the up and down motion component of the four motion mechanism of the feed dog. With particular reference to Fig. 3, the four motion component corresponding respectively to downward and upward displacement of the feed dog 16 are the motion components which are employed to reciprocate the knife 30. The remaining motion components correspond to the forward and return strokes of the feed dog merely brings about translation of the circular cam element 56 in the cam follower slot 52. Accordingly the cutting action may be characterized as follows: During the forward feeding stroke, the knife 30 is in the up position of its reciprocation, as illustrated in Fig. 3. When the feed dog reaches the extreme of its forward travel, as illustrated in Fig. 3 and begins its downward stroke, the knife begins its downward reciprocation. During the rearward travel of the feed dog, the knife is in its down or retracted position. Finally during the upward stroke of the feed dog, the knife is reciprocated upwardly. It will of course be appreciated that the four motion feed path is not quite rectilinear but is usually elliptical.

The cutter 30 operates against a stationary cutting block 60 in the form of an insert to' the throat plate 12 which presents a stationary cutting or knife edge 60a at one side of the reciprocating cutter 30. The cutter in turn includes a vertically extending knife edge 30a which is formed at the inner side of a reduced neck section 30b which edge lies generally in the same vertical plane as the 4 needle 18 and in the transverse plane of translation which the needle 18 moves in for the zigzag stitching. Additionally, the cutter includes an inclined foreshortened nose 30c which is directed forwardly, that is toward the operator. The undersurface 30d of the nose is provided with a bevel 30d which is directed downwardly and to the left, as illustrated in Fig. 2. The cutter is constructed to effectively shear the material moving past it in a vertical line of action corresponding generally to the reduced neck 30b having the shearing or cutting edge 30a.

Cooperating with the cutter 30 is a separator, generally designated by the reference character 62, which is arranged to separate superposed pieces of material whereby the lowermost piece of material may be subjected to the action of the cutter 30 during feed of both the pieces through the sewing machine. The illustrated separator is constructed -to provide minimum interference with the stitching operation, yet achieve its intended function. Specifically, the separator 62 includes a laterallyextending plate 64 of thin resilient material which has a leading portion 64a overlying and bearing against the nose 30a of the cutter 30 and a hook end 641; engaged about one side of the throat plate 112. The plate 64 is dome-shaped in its transverse section, as seen best in Fig. 3, to assure the smooth flow 0f the upper ply or plies of material over the cutter 30. The separator 62 is fabricated of resilient material so that it bears against and follows the cutter during its reciprocation; in a sense, the separator may be described as spring biased into contact with the cutter, yet tracking with the cutter in its various positions of reciprocation. Thus, the separator 62 allows for the requisite reciprocation of the cutter 30 and achieves its intended function of maintaining certain of the plies out of the path of the cutter. Yet when the stitching operation is being achieved and maximum steerability is required, the separator translates downwardly along with the feed dog 1:? and the cutter 3% When the needle 18 is in its full down position, minimum obstruction is presented to the stitching together of the superposed plies and there is a greater assurance of proper stitching. When it is necessary to make a sharp turn, the needle 18 is brought to its full down position, and with the needle penetrated through the assembly, the turn is negotiated. At this time, the cutter 30 and the separator 62 are retracted to present minimum obstruction to negotiation of the turn.

A more thorough understanding of the present invention will be had by conjoint reference to Figs. 3 and 6 which show a bottom ply or piece of material, such as the netting 70 which is to be stitched to a top piece of trimming, such as the lace 72, along the scalloped edge 72a of the lace. As seen in Fig. 3 the lace 72 is directed over the knife by the dome-shaped separator 62 which is seen in Fig. 2 to terminate along the side of the cutter adjacent the needle 18. On the other hand, the netting 72 is allowed to pass through the knife and to be severed in the transverse plane of the needle 18 along the cutting edge 39a. The action of the cutter is seen in Fig. 6 to produce a scalloped edge 70:: on the netting 70 which corresponds to the scalloped edge 72a which the operator follows in effecting the zig-zag stitching 74. The cut away material, designated by the reference character '75, is of course waste and is discarded to leave the netting 70 and the lace 72 joined together along the scalloped edge 72a by the zigzag stitching 74 with a finished cut edge 70a on the undersurface of the assembly which follows the scalloping. As seen in Fig. 6, the cut edge 70a is spaced outwardly from the adjacent limits of the stitching 74 to provide adequate body for the stitching. It will of course be appreciated that the showing of Fig. 6 has been greatly exaggerated to demonstrate the several aspects of the present invention. When a sharp change of a direction occurs, for example at the point or apex 72b between successive scallops, the needle 18 is brought to the full down position in which position the feed dog is retracted below the plate and the assembly of the separator and the cutter are in their full down position. With the parts effectively retracted, the operator pivots the stitched assembly about the needle to change direction and thereafter continues the stitching operation.

A latitude of modification and substitution is intended in the foregoing disclosure and in certain instances some features of the invention will be used without a corresponding use of other features. Accordingly it is appropriate that the appended claims be construed broadly and in a manner consistent with the spirit and scope of the present invention.

What I claim is:

1. In combination with a sewing machine including a needle operative along a vertically-extending line of action, a reciprocating cutter arranged at one side of said needle and spaced therefrom, said cutter having a cutting edge disposed substantially in a common vertical plane with said needle which plane extends transversely of the feed path for pieces of material through said machine, means operatively connected to said cutter for reciprocating said cutter to move said cutting edge in said vertical plane, and means overlying said cutter and arranged to separate superposed pieces of material whereby the lower piece of material may be subjected to the action of said cutter during feed of both said pieces through said sewing machine along said feed path.

2. In combination with a zig-zag stitching machine including a needle operative in a vertically extending plane transverse to the direction of material feed, a reciprocating cutter arranged at one side of said needle and spaced therefrom to allow for sidewise movement of said needle, said cutter having a cutting edge disposed substantially in said vertical plane, means operatively connected to said cutter for reciprocating said cutter to move said cutting edge in said vertical plane, and means including a separator plate overlying said cutter and arranged to separate superposed pieces of material whereby the lower piece of material may be subjected to the action of said cutter during feed of both said pieces through said sewing machine.

3. An appliqueing device for stitching trimming to a piece of material along a prescribed stitch line and concurrently cutting away excess portions of said piece of material at one side of said stitch line comprising zig-zag stitching mechanism including a needle, means for reciprocating said needle in a vertical plane and for oscillating said needle laterally in said vertical plane and at right angles to said stitch line, a feed dog, drive means operatively connected to said feed dog for imparting motion thereto whereby the assembly of said piece of material and said trimming may be fed past said needle for stitching together, a reciprocating cutter arranged at one side of said needle and including a cutting edge operative substantially in said vertical plane, means operatively connected to said drive means for reciprocating said cutter, and separating means overlying said cutter and arranged to guide said trimming over said cutter whereby the piece of material may be subject to the action of said cutter during appliqueing, the cutting taking place along a cutting line tracking with said stitch line but offset therefrom to said one side of said needle.

4, An appliqueing device for stitching trimming to a piece of material along a prescribed stitch line and concurrently cutting away excess portions of said piece of material at one side of said stitch line comprising zig-zag stitching mechanisms including a needle, means for reciprocating said needle laterally in said vertical plane and at right angles to said stitch line, a feed dog, drive means operatively connected to said feed dog for imparting motion thereto whereby the assembly of said piece of material and said trimming may be fed past said needle for stitching together, a reciprocating cutter arranged at one side of said needle and including a cutting edge operative substantially in said vertical plane, means operatively connected to said drive means for reciprocating said cutter, and separating means overlying said cutter and arranged to guide said trimming over said cutter whereby the piece of material may be subject to the action of said cutter during appliqueing, the cutting taking place along a cutting line tracking with said stitch line but oitset therefrom to said one side of said needle, said separating means including a plate fabricated of resilient material bearing against said cutter and tracking therewith during reciprocating of said cutter.

References Cited in the file of this patent UNITED STATES PATENTS 959,275 Wales May 24, 1910 2,064,598 Fabian et a1 Dec. 15, 1936 2,472,862 Sigoda June 14, 1949 

